The invention relates generally to processing digital images for recognizing information by using Optical Character Recognition (OCR). The invention applies more particularly to processing digital images of mailpieces for automatically recognizing postal addresses by using OCR, with a view to automatically sorting such mailpieces in postal sorting installations.
The terms “mail” and “mailpieces” are to be understood generally as being letters, large-format flat articles or “flats” such as magazines, and also packets, parcels, or the like that can be processed by postal operators.
The invention thus relates more particularly to a method of processing digital images, in which method a digital image is taken of a mailpiece bearing certain information and OCR is applied to the information in said image by using an OCR reader. Patent Document EP 1 129 792 discloses a method of processing images of mailpieces. In that method, on the basis of an image of a mailpiece, an address in the image is recognized by using OCR, and that address is printed on the mailpiece in the form of a bar code encoding the delivery postal address of the mailpiece. In the article entitled “Technology Trend of Postal Automation” dating from 1999, various types of OCR are presented for reading postal addresses on mailpieces. Patent Document EP 1 840 799 describes a method of reading postal addresses on mailpieces. In that method, OCR is used that is specialized as a function of the results of dual binarization of the image of each mailpiece.
Incorporating additional capacities for recognizing postal addresses on mailpieces in an existing postal sorting machine is always very complex and costly because it can call into question the computer architectures in the installation, and the communications protocols for communication between the various pieces of equipment in the installation. Such incorporation can even make it necessary to change the format of the data transmitted between the pieces of equipment, and also to change the software applications in order to take account of the new information exchanged between the pieces of equipment. Very often, all these constraints lead users of such installations to leave them as they are rather than to upgrade them to benefit from the latest technological developments.